Openldap 2.1.3 and freeradius 0.7

Hi list,
I try to get freeradius to work with openldap 2.1.3
I get an error when the radius-server connects to the ldap: "requested
protocol version not allowed"
What does this message mean? can I configure something in openldap or must
I look in the freeradius-config?
Kind regards,
Chris
--
Christian Pohl